Electronic device

ABSTRACT

A power switch and connector that are conventionally included in a body are formed in spaces created at the outer ends of the shafts of hinges other than the body and a display, whereby the body is thinned. Electronic device comprises a body, a display, and a hinge that joins the body and display so that they can be freely opened or closed. A power switch is formed at an end of the shaft of the hinge. Furthermore, the electronic device comprises the body, the display, and another hinge that joins the body and display so that they can be freely opened or closed. A port of a connector opens at an end of the shaft of the hinge.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a divisional of U.S. application Ser. No.12/240,229, filed Sep. 29, 2008, which is a divisional of U.S.application Ser. No. 10/970,290, filed Oct. 21, 2004, now U.S. Pat. No.7,489,507, issued Feb. 10, 2009. This application is based upon andclaims the benefit of priority from prior Japanese Patent ApplicationNo. 2003-363925, filed Oct. 23, 2003. The entire contents of each ofthese documents are incorporated herein by reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to an electronic device having a hingethat joins a body and a display. More particularly, the presentinvention is concerned with the electronic device in which an outerspace in the hinge is effectively utilized.

2. Description of the Related Art

Notebook computers have been known for some time as an electronic devicewith a body and a display which can freely be opened away from the bodyand closed onto the body.

In the electronic device, for example, as disclosed in Patent Document1, a power switch is flush with a keyboard included in the body.Moreover, in the electronic device disclosed in Patent Document 2, thepower switch is juxtaposed with other operation switches on the lateralside of the body. Moreover, since a motherboard is incorporated in thebody, connectors allowing linkage with external equipment or acommunication line are disposed on the lateral side or rear side of thebody.

[Patent Document 1] Japanese Unexamined Patent Publication No.2002-108505

[Patent Document 2] Japanese Unexamined Patent Publication No. 2002-7048

In recent years, the electronic device has become more and more compact.There is difficulty in preserving a space, in which components aredisposed, in a body and a display alike. Moreover, for realization ofthinner equipment, it proves effective to limit the number of componentsto be incorporated in the body. The present inventor et al. have givenattention to a space created at an outer end of the shaft of a hingeother than the body and the display. A power switch or a connector thatare conventionally included in the body is disposed in the space inefforts to thin the body.

SUMMARY OF THE INVENTION

In one aspect, an electronic device in accordance with the presentinvention comprises a body, a display, and a hinge that joins the bodyand display so that they can freely be opened or closed. A power switchis formed at an edge of the shaft of the hinge.

In another aspect, the electronic device in accordance with the presentinvention comprises a body, a display, and a hinge that joins the bodyand display so that they can be freely opened or closed. A port of aconnector opens at an end of the shaft of the hinge.

As mentioned above, since the power switch or connector is disposed in aspace at an end of the shaft of a hinge which has been left unused as aso-called dead space in the past, the freedom in disposing components inthe body or display is expanded accordingly. By devising the layout ofthe components, thinning of the body and display is facilitated.

According to the electronic device in which the present invention isimplemented, a power switch is disposed at an end of the shaft of ahinge. A space in the electronic device that has not been used at all inthe past can be utilized effectively. The number of components to beincorporated in the body can be reduced, and the freedom in laying outcomponents is expanded accordingly.

Consequently, the body can be further thinned.

Moreover, since the power switch is disposed away from a keyboard andother operation buttons, the power switch can be prevented from beingpressed by mistake and accurately manipulated.

Moreover, according to the electronic device in which the presentinvention is implemented, a port of a connector opens at an end of theshaft of a hinge. A space present in electronic device that isconventionally not used at all can be utilized effectively. The numberof components to be incorporated in a body can be reduced. The freedomin laying out components is expanded accordingly.

Consequently, the body can be further thinned.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of an electronic device according to anembodiment of the invention in an opened state;

FIG. 2 is a perspective view of the electronic device in a closed state;

FIG. 3 is a plan view of the inside of a lower section 27 of a case 26of the electronic device;

FIG. 4 is a side view of the lower section 27 as seen along the arrows[4] and [4] of FIG. 3;

FIG. 5 is a plan view of the built-in components disposed in the case26;

FIG. 6 is a plan view of one surface of a motherboard to be fitted intothe case 26;

FIG. 7 shows the other surface of the motherboard shown in FIG. 6;

FIG. 8 is a plan view of connectors and a flexible wiring board providedin the case 26;

FIG. 9 is a front view of the connectors and the flexible wiring boardof FIG. 8;

FIG. 10 is an enlarged front view of the connectors shown in FIGS. 8 and9;

FIG. 11 is a plan view of a keyboard fitted into the case 26;

FIG. 12 is a front view of the keyboard;

FIG. 13 is a rear view of the keyboard;

FIG. 14 is a left-side view of the keyboard;

FIG. 15 is a right-side view of the keyboard;

FIG. 16 is a back side view of the keyboard;

FIG. 17 is a plan view of the inside of the upper section 28 of the case26;

FIG. 18 is a schematic cross section of the inside of the case 26 whereheat-generating components are placed;

FIG. 19 is a plan view of the inside of a case 22;

FIG. 20 is a side view of the case 22 as seen along the arrows [20] and[20] in FIG. 19;

FIG. 21 is a plan view of a liquid crystal panel and an inverter circuitboard fitted in the inside of the case 22;

FIG. 22 is an enlarged plan view of a principal part of the liquidcrystal panel being housed in the case 22;

FIG. 23 is an enlarged view of one of the two constituent parts ofhinges formed at the back of the case 22;

FIG. 24 is an enlarged view of the other constituent part of the hingesformed at the back of the case 22;

FIG. 25 is a schematic diagram showing a construction of a power switchinstalled in the constituent part of the hinge shown in FIG. 23;

FIGS. 26A and 26B are schematic cross sections of the laminatedstructure of the case 22 of the electronic device according to thepresent embodiment;

FIGS. 27A and 27B show the pieces of conductor foil being stuck onto thelaminated layer of FIGS. 26A and 26B;

FIG. 28 shows a resin material being stuck onto edge portions of thelaminated layers shown in FIG. 26;

FIG. 29 is an enlarged view of the rear portion of the electronic devicein an opened state according to the present embodiment; and

FIG. 30 is an enlarged view of the front edge portion of the electronicdevice in a closed state according to the present embodiment.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Now, an embodiment of an electronic device in accordance with thepresent invention will be described below. The embodiment is a notebookcomputer.

FIGS. 1 and 2 show the outer appearances of the electronic device 1 ofthe present embodiment. The electronic device 1 comprises a body 3, adisplay 5, and two hinges “h” which fasten the display 5 to the body 3.

The display 5 pivots on the hinges “h” to open away from the body 3 andclose onto the body 3. In FIG. 1, the display 5 is opened away from thebody 3. In FIG. 2, the display 5 is closed onto the body 3.

The body 3 has a case 26. Disposed in the case 26 as shown in FIG. 5 area keyboard 11, a motherboard 30, a hard-disk drive 32, a PC card slot34, and connectors 40 a-d.

The keyboard 11 is an input unit of the electronic device 1. Themotherboard 30 is the substantially main functional component of theelectronic device 1 and receives signals inputted through the keyboard11 and makes various kinds of processing such as arithmetic processing,control processing, image processing, and processing to output signalsto the display 5.

The motherboard 30 serves as a control circuit board to controlindividual components such as the keyboard 11 and the display 5, too.

The case 26 comprises an upper section 28 and a lower section 27. FIG. 3is a plan view of the inside of the lower section 27.

FIG. 4 is a side view of the lower section 27 as seen along the arrows[4] and [4] of FIG. 3.

The lower section 27 looks like a flat box and has an almost rectangularbottom plate 27 a, right and left side plates 27 b and 27 d, and a backplate 27 c. As shown in FIGS. 3 and 4, the side and back plates 27 b-dare erected on the three sides of the bottom plate 27 a.

The back plate 27 c is erected on the back side of the bottom plate 27 aand has outward-protruding constituent parts 42 a and 42 b of the hinges“h” as shown in FIGS. 3 and 4.

As shown in FIGS. 3 and 4, there are cuts 43 a-d in the left side plate27 b for the connectors 40 a-d and a cut 43 e in the right side plate 27d for the PC card slot 34.

The inside of the bottom plate 27 a is provided with a resin mold 45,which is raised from the inside surface of the bottom plate 27 a toreinforce the lower section 27 against bending and twisting.

A heat-transmitting sheet 47 is stuck on the inside surface of thebottom plate 27 a. The heat-transmitting sheet 47 is positioned near tothe center between the right and left sides of the bottom plate 27 a andone-sided toward the back side of the bottom plate 27 a.

The heat-transmitting sheet 47 is, for example, a graphite sheet 0.1 to1.0 mm thick. Because the heat-transmitting sheet 47 is positioned in anarea where the mold 45 does not exist, the heat-transmitting sheet 47does not float, but is closely stuck onto the inside of the bottom plate27 a; accordingly, the heat from heat-generating components to bedescribed later is diffused effectively through the lower section 27.

An elastic sheet 48 is laid between the heat-transmitting sheet 47 andthe bottom plate 27 a. The elastic sheet 48 is rectangular and largerthan the heat-generating components. The elastic sheet 48 is positionedsubstantially in the middle of the lateral width of the lower section 27within about a half of the bottom 27 a near the wall portion 27 c.

To be specific, the elastic sheet 48 is 0.5-3.0 mm thick and made ofPoron (of Rogers Inoac Corporation) which is high-density polyurethanefoam whose cells are fine and uniform.

An insulating sheet 49 is overlaid on the heat-transmitting sheet 47;accordingly, short circuits between the heat-transmitting sheet 47,which is made of graphite and conductive, and the motherboard, which isput on the heat-transmitting sheet 47, are prevented.

The insulating sheet 49 is, for example, a transparent thin film ofpolyphenylene sulfide. It is as thin as, for example, 0.05-0.3 mm;therefore, it does not prevent heat transmission from theheat-generating components to the heat-transmitting sheet 47.

The lower section 27 is made of CFRP (carbon fiber reinforced plastics).To be specific, the CFRP consists of six layers 51 a, 51 b, 52 a, 52 b,53 a, and 53 b as shown in FIG. 26.

As shown in FIG. 26A, the six layers 51 a, 51 b, 52 a, 52 b, 53 a, and53 b are pressed together.

Each layer is made of long carbon fibers solidified by epoxy resin. Allthe fibers of each layer are put side by side in one and the samedirection.

To be specific, the carbon fibers of the innermost layers 51 a and 51 bare laid in the longitudinal direction of the electronic device 1.Accordingly, the carbon fibers of the layer 51 a are parallel to thoseof the layer 51 b.

The carbon fibers of the intermediate layers 52 a and 52 b are laid inthe lateral direction of the electronic device 1.

The carbon fibers of the outermost layers 53 a and 53 b are laid in thedirection at angles of 45° with the longitudinal and lateral directionsof the electronic device 1. Accordingly, the carbon fibers of the layer53 a are parallel to those of the layer 53 b.

With the above laminated structure, the thin lower section 27 hassufficient strength. As the lower section 27 is thin, the electronicdevice 1 is also thin, which is an advantage for portable electronicdevices in particular.

As shown in FIG. 28, an insulating layer 56 is formed on the insidesurface of the bottom plate 27 a. The insulating layer 56 is made of,for example, nylon (a trade name of Du Pont).

The insulating layer 56 prevents short circuits between the lowersection 27, which is made of CFRP (carbon fiber reinforced plastics)containing conductive carbon fibers, and the motherboard 30 fitted inthe lower section 27.

When the insulating layer 56 made of nylon is heated, it softens andbecomes adhesive. By making use of the adhesiveness of the insulatinglayer 56, the mold 45 is stuck and fixed to the insulating layer 56. Themold 45 has bosses with threaded holes, etc.

As shown in FIG. 28, the front edge of the lower section 27 is providedwith a resin cover 45 a. By making use of the adhesiveness of theinsulating layer 56, the cover 45 a is stuck onto the insulating layer56 to cover the front edge of the lower section 27. Thus, loose ends ofcarbon fibers, if any, at the front edge of the lower section 27 arecovered up.

As shown in FIG. 3, because the resin cover 45 a extends along the frontedge of the lower section 27, it serves as a beam, too, reinforcing thelower section 27 against bending and twisting.

The resin cover 45 a and the mold 45 are made of nylon as well as theinsulating layer 56; accordingly, the cover 45 a and the mold 45 arestuck on the insulating layer 56 sufficiently. As shown in FIG. 28, agroove 54 is made in the surface of the resin cover 45 a which comes incontact with the insulating layer 56. When the insulating layer 56 isheated and softened and the cover 45 a is stuck on the insulating layer56, surplus softened, adhesive nylon enters into the groove 54.

Thus, the surplus softened, adhesive nylon is prevented from leaking outthrough the joint between the lower section 27 and the cover 45 a. Ifthe surplus softened, adhesive nylon leaks out, the appearance of theelectronic device 1 is spoiled.

Because the right and left side plates 27 b and 27 d are erected on theright and left sides, respectively, and the back plate 27 c is erectedon the back side of the bottom plate 27 a, these plates 27 b, 27 c, and27 d play the role of the cover 45 a.

Now, the motherboard to be fitted in the lower section 27 will bedescribed below by referring to FIGS. 6 and 7. FIG. 6 shows the uppersurface of the motherboard 30; FIG. 7, the lower surface. A centralprocessor 58 is mounted on the upper surface. An image processor 60 anda plurality of semiconductor memories 62 are mounted on the lowersurface. Although not shown in FIGS. 6 and 7, many other components aremounted on both the surfaces of the motherboard 30.

The central processor 58 and the image processor 60 are semiconductorsand generate heat when they function. The central processor 58 and theimage processor 60 are so positioned that they do not overlap with eachother.

The motherboard 30 comprises a multi-layer printed circuit board and thecentral processor 58, the image processor 60, the semiconductor memories62, and other components (not shown) mounted on both the surfaces of amulti-layer printed circuit board and is the substantial body of theelectronic device 1 in terms of functions of the electronic device 1.

The multi-layer printed circuit board is made by the buildup method asfollows. A two-layer printed circuit board (hereinafter “intermediatetwo-layer printed circuit board”) is laid on each of the upper and lowersurfaces of an innermost two-layer printed circuit board. A single-layerprinted circuit board is laid on the upper surface of the upperintermediate two-layer printed circuit board; a single-layer printedcircuit board, on the lower surface of the lower intermediate two-layerprinted circuit board. A single-layer printed circuit board is laid onthe upper surface of the upper single-layer printed circuit board; asingle-layer printed circuit board, on the lower surface of the lowersingle-layer printed circuit board. Thus, a ten-layer printed circuitboard is made. The buildup method enables us to do wiring efficientlyand high-density mounting of parts.

The connectors 40 a-d shown in FIGS. 8-10 are also fitted in the lowersection 27. The connectors 40 a-d are connected to the motherboard 30through a flexible wiring board 67. Namely, the connectors 40 a-d areconnected to wires at one end of the flexible wiring board 67, and theother end 67 a of the flexible wiring board 67 is inserted into aconnector mounted on the motherboard 30.

As shown in FIG. 10, the connector 40 b is provided two flanges 64protruding from the right and left shorter sides of its socket. Byfixing the flanges 64 to the left side plate 27 b by using, for example,screws, the connector 40 b can be fixed to the left side plate 27 b. Theconnector 40 c has the same flanges 64 as the connector 40 b.

The keyboard 11 shown in FIGS. 11-16 is fitted to the lower section 27.FIG. 11 is a plan view of the keyboard 11. FIGS. 12 and 13 are front andrear views, respectively, of the keyboard 11. FIGS. 14 and 15 are leftand right side views, respectively, of the keyboard 11. FIG. 16 is abottom view of the keyboard 11.

The keyboard 11 comprises a case 37, input keys 13, a pointing device 14called “track point,” and a cover 36.

The case 37 is made of, for example, magnesium and in the shape of aflat box, having a key-arrangement area and side plates erected aroundthe key-arrangement area.

The key-arrangement area is in the shape of an almost rectangular flatplate and the side plates are formed, as a single piece, at the right,left, top, and bottom sides of the key-arrangement area.

As described above, the case 37 is not a flat plate, but in the shape ofa flat box, having the side plates; accordingly, its rigidity is high.When a user presses keys 13, the case 37 does not warp, giving goodrepulsion to the fingers of the user. Thus, the feeling of key operationis good.

The four sides of each key of an ordinary keyboard are inclined, whereasthe four sides of input keys 13 are not inclined. Accordingly, theoccupancy area of each input key 13 is smaller than that of an ordinarykey. Accordingly, the gaps between input keys 13 can be widened toprevent the user from pressing wrong input keys 13.

The cover 36 has cuts in it, and the input keys 13 and the pointingdevice 14 are exposed through the cuts. The key-arrangement area iscovered with the cover 36. Thus, the gaps between input keys 13 arecovered and, hence, dust and water are prevented from entering throughthe gaps. The cover 36 and the input keys 13 are made of, for example,ABS resin.

Now, the upper section 28 of the case 26 will be described below byreferring to FIG. 17. FIG. 17 is a plan view of the inside of the uppersection 28 which faces the inside of the lower section 27 shown in FIG.3.

The upper section 28 is almost rectangular and has approximately thesame area as the lower section 27. The upper section 28 has a large cut80 in its front area wherein the input keys 13 and the pointing device14 are arranged.

The reference numeral 81 in FIG. 17 is a covered area.Outward-protruding constituent parts 74 a and 74 b of the hinges “h” areformed at the back side of the covered area 81.

A heat-transmitting sheet 72 is stuck to the inside of the covered area81. The heat-transmitting sheet 72 is positioned near to the centerbetween the right and left sides of the covered area 81.

The heat-transmitting sheet 72 is made of, for example, graphite and0.1-1.0 mm thick. The heat-transmitting sheet 72 is shaped and has cutsin it so as to avoid bosses and ribs erected inside the covered area 81.Thus, the covered area 81 is not floated over the inside surface of thecovered area 81, but closely stuck onto the inside surface; accordingly,the heat from heat-generating components is effectively diffused throughthe upper section 28.

An elastic sheet 83 is laid between the heat-transmitting sheet 72 andthe inside surface of the covered area 81. The elastic sheet 83 isrectangular and larger than the heat-generating components in contactwith the heat-transmitting sheet 72. The elastic sheet 83 is positionednear to the center between the right and left sides of the covered area81.

To be specific, the elastic sheet 83 is 0.5-3.0 mm thick and made ofPoron (of Rogers Inoac Corporation) which is high-density polyurethanefoam whose cells are fine and uniform.

An insulating sheet (not shown) is overlaid on the heat-transmittingsheet 72; accordingly, short circuits between the heat-transmittingsheet 72, which is made of graphite and conductive, and the motherboard30, which is put on the heat-transmitting sheet 72, are prevented.

The insulating sheet is, for example, a transparent film ofpolyphenylene sulfide. It is as thin as, for example, 0.05-0.3 mm;therefore, it does not prevent heat transmission from theheat-generating components to the heat-transmitting sheet 72.

The lower section 27 and the upper section 28 are coupled by, forexample, screws. At this time, the keyboard 11, motherboard 30,hard-disk drive 32, and PC card slot 34 are fitted in the inside of thelower section 27.

The cooling mechanism for the central processor 58 and the imageprocessor 60, which are mounted on the upper and lower surfaces,respectively, of the motherboard 30 and generate heat, will be describedbelow by referring to FIG. 18.

The lower surface, on which the image processor 60 is mounted, of themotherboard 30 faces the inside of the lower section 27. The uppersurface, on which the central processor 58 is mounted, faces the insideof the upper section 28.

The image processor 60 is in contact with the part of theheat-transmitting sheet 47 raised by the elastic sheet 48. In this way,the image processor 60 is put in close contact with theheat-transmitting sheet 47 by the elasticity of the elastic sheet 48.Thus, air is precluded from between the image processor 60 and theheat-transmitting sheet 47 and the heat from the image processor isefficiently transmitted to the heat-transmitting sheet 47.

The heat transmitted to the heat-transmitting sheet 47 is diffusedthrough the heat-transmitting sheet 47 and the lower section 27. Thus,overheat of the image processor 60 is prevented.

The central processor 58 is in contact with the part of theheat-transmitting sheet 72 lowered by the elastic sheet 83. In this way,the central processor 58 is put in close contact with theheat-transmitting sheet 72 by the elasticity of the elastic sheet 83.Thus, air is precluded from between the central processor 58 and theheat-transmitting sheet 72 and the heat from the central processor 58 isefficiently transmitted to the heat-transmitting sheet 72.

The heat transmitted to the heat-transmitting sheet 72 is diffusedthrough the heat-transmitting sheet 72 and the upper section 28. Thus,overheat of the central processor 58 is prevented.

The central processor 58 and the image processor 60 are so positionedthat they do not overlap with each other and, hence, the heat from thecentral processor 58 and the image processor 60 is not concentrated at asingle spot. Beside, this arrangement of the central processor 58 andthe image processor 60 enables the reduction of the distance between thelower section 27 and the upper section 28 and, hence, the reduction ofthe body 3.

The semiconductor memories 62 (see FIG. 7) mounted on the lower surfaceof the motherboard 30 are also in contact with the heat-transmittingsheet 47 and their heat is diffused through the heat-transmitting sheet47.

The hard-disk drive 32 as that is a storage device, which is positionedto the left of the motherboard 30 in FIG. 5, will be described below.

As shown in FIG. 3, ribs 46 are formed in the four corners of a harddisk drive-mounting space 44 in the lower section 27. In addition, asshown in FIG. 17, ribs 78 are formed in the four corners of a hard diskdrive-mounting space 76 in the upper section 28.

Accordingly, the hard-disk drive 32 is supported by the ribs 46 and 78,a gap of the height of ribs 78 kept between the top surface of thehard-disk drive 32 and the inside surface of the upper section 28, a gapof the height of ribs 46 kept between the bottom surface of thehard-disk drive 32 and the inside surface of the lower section 27.

There are small gaps in spots, where the connectors 40 a-d (see FIG. 5)are mounted to expose their sockets, of the left side plates of thelower section 27 and the upper section 28. The inside and the outside ofthe case 26 are connected by the small gaps. The space in which themotherboard 30 is fitted and the outside of the case 26 can be connectedby the small gaps and the gaps on and under the hard-disk drive 32.

Accordingly, the discharge of heat from the central processor 58 and theimage processor 60 can be accelerated. Besides, the hard-disk drive 32can be air-cooled.

The connectors 40 a-d are connected to the motherboard 30 through theflexible wiring board 67 (see FIG. 8). The flexible wiring board 67 isrouted through the gap between the bottom surface of the hard-disk drive32 and the inside surface of the lower section 27.

Because the connectors 40 a-d are not mounted directly on themotherboard 30, shock at the time of connection and disconnection ofexternal cables to and from the connectors 40 a-d is absorbed by theflexible wiring board 67. Thus, the shock is not transmitted to themotherboard 30, damage to and positional slippage of the motherboard 30prevented.

As shown in FIGS. 8 and 9, the connectors 40 b and 40 c are disposed sothat the right flange 64 of the connector 40 b and the left flange 64 ofthe connector 40 c overlap with each other. The two flanges 64overlapping with each other are fixed to the left side plate of thelower section 27 with, for example, a screw. Thus, the space to mountthe connectors 40 a-d is saved by the space of one flange 64.

As shown in FIG. 5, the PC card slot 34 is disposed at the right side ofthe case 26. The PC card is the standards for card-type peripheraldevices established jointly by PCMCIA (Personal Computer Memory CardInternational Association) and JEIDA (Japan Electronic IndustryDevelopment Association).

The keyboard 11 is disposed in the space along the front of the case 26.The input keys 13 and the pointing device 14 are exposed to the outsidethrough the cut 80 in the upper section 28.

As described above, the motherboard 30, hard-disk drive 32, and PC cardslot 34 are disposed in the space along the back of the case 26 and thekeyboard 11 is disposed in the space along the front of the case 26.

Cuts are made in the right and left sides of the motherboard 30 to avoidthe hard-disk drive 32 and the PC card slot 34. The keyboard 11 does notoverlap with the central processor 58 or the image processor 60 mountedon the motherboard 30 or the hard-disk drive 32 or the PC card slot 34.

As described above, because built-in components are arranged withouttheir overlapping with one another, the body 3 can be made thin.

Part of the motherboard 30 is placed under the keyboard 11, but thecentral processor 58 and the image processor 60, which account for alarge part of the thickness of the motherboard 30, do not overlap withthe keyboard 11. Accordingly, the body 3 is not prevented from beingmade thin. An insulating sheet made of, for example, polycarbonate islaid between the part of the motherboard 30 overlapping with thekeyboard 11 and the keyboard 11 in order to prevent short circuitsbetween the case 37 of conductive magnesium and the motherboard 30. Themotherboard 30 and the keyboard 11 may be arranged so that they do notoverlap with each other at all.

Because the heat-generating central processor 58 and image processor 60do not overlap with the keyboard 11, the heat of neither the centralprocessor 58 nor the image processor 60 is transmitted to the keyboard11 to annoy the user.

Because the central processor 58 and the image processor 60 are disposedin the space along the back side of the case 26 and the keyboard 11 isdisposed in the space along the front side of the case 26, the user canoperate the keyboard 11 without touching the upper section 28 coveringthe central processor 58 and the image processor 60.

The central processor 58 and the image processor 60 are positioned nearto the center between the right and left sides of the case 26;accordingly, less heat is transmitted from the central processor 58 andthe image processor 60 to the user's right and left hands which tend tobe positioned toward the right and left sides of the keyboard 11,respectively. When the user moves the electronic device 1 with thedisplay 5 opened, the user holds the right and left sides of the part ofthe body 3 behind the keyboard 11; accordingly, less heat is transmittedfrom the central processor 58 and the image processor 60 to the hands ofthe user.

Because the most heat-generating image processor 60 is mounted on thelower surface of the motherboard 30, less heat is transmitted from theimage processor 60 to the top, or keyboard, side of the body 3, lessannoying the user.

Now, the display 5 will next be described. The display 5 comprises acase 22 (see FIG. 19), a liquid crystal panel 7 (see FIG. 21) housed inthe case 22, and an inverter circuit board 93 (see FIG. 21).

FIG. 19 is a plan view of the inside of the case 22. FIG. 20 is a sideview of the case 22 as seen along the arrows [20] and [20] in FIG. 19.The case 22 is almost rectangular and side plates are erected at theright and left sides of the case 22.

Outward-protruding constituent parts 87 a and 87 b of the hinges “h” areformed at the right and left ends of the back side of the case 22.

Molds 85 a-d are provided inside the case 22. The molds 85 a-d aredisposed so that they enclose the four sides of the case 22 andreinforce the case 22 against bending and twisting.

In the same way as the lower section 27, the case 22 is made of CFRP(carbon fiber reinforced plastics). To be specific, the CFRP consists ofsix layers 51 a, 51 b, 52 a, 52 b, 53 a, and 53 b as shown in FIG. 26.

As shown in FIG. 26A, the six layers 51 a, 51 b, 52 a, 52 b, 53 a, and53 b are pressed together.

Each layer is made of long carbon fibers solidified by epoxy resin. Allthe fibers of each layer are put side by side in one and the samedirection.

To be concrete, the carbon fibers of the innermost layers 51 a and 51 bare laid in the longitudinal direction of the electronic device 1.Accordingly, the carbon fibers of the layer 51 a are parallel to thoseof the layer 51 b.

The carbon fibers of the intermediate layers 52 a and 52 b are laid inthe lateral direction of the electronic device 1.

The carbon fibers of the outermost layers 53 a and 53 b are laid in thedirection at angles of 45° with the longitudinal and lateral directionsof the electronic device 1. Accordingly, the carbon fibers of the layer53 a are parallel to those of the layer 53 b.

With the above laminated structure, the thin case 22 has sufficientstrength. As the case 22 as well as the lower section 27 is thin, theelectronic device 1 is also thin, which is an advantage for portableelectronic devices in particular.

As shown in FIG. 28, an insulating layer 56 is formed on the insidesurface of the case 22. The insulating layer 56 is made of, for example,nylon (a trade name of Du Pont).

The insulating layer 56 prevents short circuits between the case 22 madeof CFRP containing conductive carbon fibers and the liquid crystal panel7, the inverter circuit board 93, etc. housed in the case 22.

When the insulating layer 56 made of nylon is heated, it softens andbecomes adhesive. By making use of the adhesiveness of the insulatinglayer 56, the molds 85 a-d are stuck and fixed to the insulating layer56. Because the molds 85 a-d are also made of nylon, they stick well tothe insulating layer 56.

As shown in FIG. 28, the front and back edges of the case 22 areprovided with the molds 85 a and 85 b, respectively. By making use ofthe adhesiveness of the insulating layer 56, the molds 85 a and 85 b arestuck onto the insulating layer 56 to cover the front and back edges ofthe case 22. Thus, loose ends of carbon fibers, if any, at the front andback edges of the case 22 are covered up.

Because the molds 85 a and 85 b extend along the front and back edges ofthe case 22, they serve as beams, too, reinforcing the case 22 againstbending and twisting.

As shown in FIG. 28, grooves 54 are made in the surfaces of the molds 85a and 85 b which come in contact with the insulating layer 56. When theinsulating layer 56 is heated and softened and the molds 85 a and 85 bare stuck on the insulating layer 56, surplus softened, adhesive nylonenters into the grooves 54.

Thus, the surplus softened, adhesive nylon is prevented from leaking outthrough the joints between the case 22 and the molds 85 a and 85 b. Ifthe surplus softened, adhesive nylon leaks out, the appearance of theelectronic device 1 is spoiled.

Because the case 22 has the right and left side plates, these sideplates play the role of the molds 85 a and 85 b.

The opposite of the inside surface of the case 22 in FIG. 19 is afacing, which is the surface of one of the outmost layers 53 a and 53 b.A layer of self-cure resin is formed on the facing.

The layer of self-cure resin is formed by spraying, for example, acrylicor urethane resin with cross-linked structure and high capability ofelastic recovery to the facing of the case 22.

If a flaw or dent is made in the self-cure resin layer on the facing ofthe case 22, it exists as a flaw or dent temporarily and then itdisappears gradually because of the high capability of elastic recoveryof the self-cure resin layer.

The self-cure resin used in the present embodiment is transparent andcolorless. It gives luster to the facing of the case 22 made of dullblack CFRP (carbon fiber reinforced plastics) to improve the appearanceof the case 22.

The unit consisting of the liquid crystal panel 7 and the invertercircuit board 93 shown in FIG. 21 is fitted in the inside of the case 22of FIG. 19. Because the inverter circuit board 93 does not overlap withthe liquid crystal panel 7 as shown in FIG. 21, the display 5 is thin.The thinness of the display 5 as well as the thinness of the body 3contributes to the thinness of the electronic device 1.

The liquid crystal panel 7 has a back-light unit including a lightsource, light-guiding plates, etc. A fluorescent lamp, for example, isused as the light source, which may be built in the top of the liquidcrystal panel 7.

As shown in FIG. 19, a piece of conductor foil 89 such as copper foil isstuck on the inside surface of the case 22 to earth the liquid crystalpanel 7 to the case 22.

In general, there exists a thin resin film (for example, an epoxy-resinfilm) on the surface of a base plate made of CFRP; accordingly, thesurface of the base plate does not have stable conductivity. As in FIG.27, if a piece of copper foil 89 is pressed onto a resin film 127 on thesurface of the outermost layer 53 a, the piece of copper foil 89 pushesaside the resin film 127 and sticks to the layer 53 a to secure a stableelectric connection between the piece of copper foil 89 and theconductive carbon fibers of the layer 53 a.

As shown in FIG. 22, a leaf spring 95 is fitted between the piece ofcopper foil 89 on the inside of the case 22 and a metal bracket 91 amounted on a metal frame 91 of the liquid crystal panel 7 toelectrically connect the liquid crystal panel 7 to the piece of copperfoil 89. The tip of the leaf spring 95 is in elastic contact with thepiece of copper foil 89 and the base of the leaf spring 95 is fixed tothe metal bracket 91 a by, for example, a screw.

Thus, the liquid crystal panel 7 is electrically stably connected to thecase 22 with a large area to protect the liquid crystal panel 7 fromexternal magnetic noises and prevent the magnetic noises generated bythe liquid crystal panel 7 from affecting external components anddevices.

As shown in FIG. 1, a frame 24 is fitted to the case 22 housing theliquid crystal panel 7 to expose the screen 70 of the liquid crystalpanel 7.

The hinges “h” to connect the body 3 and the display 5 will next bedescribed below.

When the lower section 27 of FIG. 3 and the upper section 28 of FIG. 17are combined, the part 42 a of the lower section 27 and the part 74 a ofthe upper section 28 are combined to become a cylinder of a hinge “h.”One hinge h (the left hinge h in FIGS. 1 and 2) is constructed when thecylinder of the case 26 is rotatably connected with the constituent part87 a of the case 22 shown in FIG. 19.

On the other hand, when the lower section 27 of FIG. 3 and the uppersection 28 of FIG. 17 are combined, the part 42 b of the lower section27 and the part 74 b of the upper section 28 are combined to becomeanother cylinder. The other hinge h (the right hinge h in FIGS. 1 and 2)is constructed when the cylinder of the case 26 is rotatably connectedwith the constituent part 87 b of the case 22 shown in FIG. 19.

As shown in FIG. 23, a hinge fitting 97 is provided on the other hingeh. One end of the hinge fitting 97 is fixed to the cylinder of the case26 by, for example, a screw. The constituent part of the case 22receives a cylindrical portion of the hinge fitting 97, and the case 22,or the display 5, is relatively rotatable about the cylindrical portionsof the hinge fittings 97.

Further, as shown in FIG. 23, a power switch 20 is provided on an edgeof the hinge's shaft (a side portion which does not face the other hingewith respect to the longitudinal direction of the axis of the hinge,namely, a side portion on the right in FIG. 23). (Also, see FIG. 2)

The power switch 20 comprises, as shown in a schematic diagram of FIG.25, a pressing operation part 101, a light-emitting element 121, aswitch 125, and a contact 123.

The pressing operation part 101 can be pressed along the longitudinaldirection of the axis of the hinge (the direction shown by the arrow inFIG. 25). The light-emitting element 121 is placed inside the pressingoperation part 101. The light-emitting element 121 is, for example, alight-emitting diode and is mounted on a surface, which faces thepressing operation part 101, of the circuit board 103 joined with thepressing operation part 101.

The switch 125 is mounted on the other side of the circuit board 103.The contact 123 provided facing the switch 125 is fixed to theconstituent part of the case 22.

As shown in FIG. 2, the pressing operation part 101 is exposed to theoutside. When the pressing operation part 101 is pressed in thedirection of the arrow in FIG. 25 by a user's finger and so on, it movestoward the contact 123 together with the circuit board 103, and thelight-emitting element 121 and the switch 125 mounted thereon.

When the switch 125 is pressed touching the contact 123, the power isturned off when the power of the electronic device 1 is on and the poweris turned on when the power of the electronic device 1 is off.

When the pressing operation part 101 is pressed sideways by the user'sfinger, the direction of the movement tends to be inclined compared towhen it is pressed downward. To cope with such a problem, the surface ofthe switch 125 which meets the contact 123 is curved. Therefore, inspite of a little inclination, the contact 123 and the switch 125 canmeet stably (for example, compared to when the surface is flat, thecontact area can be larger) and the power can be turned on or offreliably.

Incidentally, the pressing operation part 101 has substantially a roundshape, and is disposed so that the rotation axis of the hinge willpierce substantially the center of the round pressing operation part101. Consequently, when the power switch is pressed in the direction ofthe rotation axis of the hinge, the power supply is turned on or off.Since the switch 125 is pressed in the direction of the rotation axis ofthe hinge, the pressing operation part 101 that is large for thethickness of the display 5 or the body 3 can be employed. Consequently,the power switch 20 is reliably manipulated.

According to the present embodiment, the pressing operation part 101that is large for the thickness of the display 5 or body 3 is adopted.As long as the pressing operation part 101 that is pressed in thedirection of the rotation axis of the hinge is adopted, the pressingoperation part 101 (switch or button) that is larger than a switch(button) to be formed in the lateral side of the case can be formedbecause of the thicknesses of the cases 22, 24, 27, and 28 thatdetermine the shapes of the display 5 and body 3 respectively.

The usage of the space in the hinge is not limited to the power switchas it is in the present embodiment. Alternatively, a switch (button) forany purpose other than the purpose of power supply may be formed. Forexample, when electronic device includes an imaging means that has a CCDor the like, the space in the hinge may be used to form a shutter buttonrequired for producing still images or an imaging start/stop buttonrequired for producing a motion picture.

Further, if all or a part (for example, a ring portion of the outeredge) of the portion of the pressing operation part 101 exposed to theoutside is formed as a light-transmission part made of transparent resinmaterial, the light from the light-emitting element 121 can be guided tothe outside through such a light-transmission part. Accordingly, whenthe power is on, for example, a red light can be turned on to have auser confirm its state visually. Alternatively, when in a power-savingstandby state, a green light can be turned on and off to have the userconfirm its state visually.

The light transmission part of the pressing operation part 101 is alwaysexposed to the outside regardless of the electronic device 1 beingopened or closed. Therefore, even if the display 5 is closed while thepower is on, the state can be checked by the light visible through thelight transmission part.

Also, when carrying the electronic device 1 in a bag or so with thedisplay 5 closed, the pressing operation part 101 may be pressed by anarticle in the bag. Accordingly, in the present embodiment, as in FIG.23, a closed-state detecting switch 105 is provided on the constituentpart of the case 22, and a closed-state detecting contact 106 isprovided on the hinge fitting 97 as a single piece.

When the display 5 is closed onto the body 3 by the relative rotation ofthe constituent part of the case 22 and the hinge fitting 97, theclosed-state detecting switch 105 and the closed-state detecting contact106 meet, turning on the closed-state detecting switch 105. Theclosed-state detecting switch 105 is kept turned on while the display 5is closed onto the body 3.

Accordingly, when the closed-state detecting switch 105 is on, that is,when the display is closed, the electronic device 1 can be preventedfrom being turned on even if the pressing operation part 10 is pressed.Alternatively, when it is closed while the power is on and theclosed-state detecting switch 105 is turned on, it becomes possible toautomatically turn the power off or to send the electronic device 1 intoa power-saving standby state.

Incidentally, a control mode is not limited to the mode of controllingthe power supply according to whether the display is open or closed, butany other control mode may be adopted.

For example, when electronic device has an imaging means that includes aCCD, the action of a shutter button required for producing still imagesor an imaging start/stop button required for producing a motion picturemay be controlled based on whether the case is open or closed. Forexample, control is extended so that when the case is closed, even ifthe button is pressed, a still image or a motion picture will not beproduced.

Incidentally, the means for detecting whether the display 5 is open orclosed is not limited to the one employed in the present embodiment, butany other means will do. For example, a magnetic body included in thedisplay 5, and a Hall sensor that is located in a region in the body 3in which the Hall sensor is opposed to the magnetic body and thatdetects a magnetic field strength may be used to detect whether thedisplay is open or closed.

Further, as in FIG. 24, a connector 19 for an AC adapter is provided onthe edge (side portion on the left in FIG. 24) of the shaft of the hingeopposite the hinge in which the power switch 20 is provided (Also, seeFIG. 1). A socket for the connector 19 is always exposed to the outsideregardless of the opened and closed state of the electronic device 1.

Moreover, the connector 19 is disposed so that the rotation axis of thehinge and the axis of the connector 19 will be aligned with each other.

Since the port of the connector 19 opens in the direction of therotation axis of the hinge, the connector 19 that is large for thethickness of the display 5 or body 3 can be employed.

According to the present embodiment, the connector 19 that is large forthe thickness of the display 5 or body 3 is employed. As long as theport of the connector opens in the direction of the rotation axis of thehinge, a connector larger than the one formed in the lateral side of anyof the cases 22, 24, 27, and 28, which determine the shapes of thedisplay 5 and body 3 respectively, can be formed because of thethicknesses of the cases.

The usage of the space in the hinge is not limited to the connector forconnection of an AC adaptor as it is in the present embodiment. Aconnector for any purpose other than the purpose of power supply may beformed. For example, a connector for connection of a headphone may beformed. Moreover, the shape of the port of the connector is not limitedto a round but may be a rectangle. For example, a connector for pluggingin of a universal serial bus (USB) 2.0 may be formed.

As in FIG. 24, a cable 112 for connecting the connector 19 with themotherboard 30 of the body 3 is not directed straight from theconnection with the connector 19 to the side of the body 3 (lowerposition in FIG. 24). On the contrary, the cable 112 detours around thearea near the connection with the connector 19 so that it forms a loopon the side of the display 5 and is drawn to the side of the body 3.

The detouring portion of the cable 112 forms a loop being guided by aboss 114 erected inside the case 22 and guide members 118, 119 a, 119 b.

Accordingly, even if opening and closing of the display 5 away from andonto the body 3 are repeated, the connection (soldered, for example) tothe connector 19 of the cable 112 is prevented from receiving aconcentrated excessive load such as twisting and pulling, thereby abreak in the cable being prevented.

Further, the guide members 119 a and 119 b restrict the rising of thedetouring portion of the cable 112 from the inside surface of the case22 so that the looped detouring portion can be held stably.

Further, the previously described power switch 20 shown in FIG. 23 isconfigured such that a cable (not shown) connected to the connector 110via the flexible wiring board 108 formed on the inside surface of thecase 22 is drawn to the side of the body 3. Therefore, again, the cableis not drawn directly from the power switch 20 to the body 3. This isbecause the previously described inverter circuit board 93 is notprovided on the inside surface of the case 22 on this side and there isenough space for arranging the above flexible wiring board 108 and theconnector 110.

As described above, the power switch 20 and the connector 19 areprovided on the edge portion of the shaft of the hinge, which has notbeen used at all, namely, a dead space. Therefore, components of thebody 3 and the display 5 can be positioned more freely. By suitablyarranging those components, the body 3 and the display 5 can be madethinner as described above. Further, since the power switch 20 ispositioned away from the keyboard 11 and other operation buttons 15 a-15c (see FIG. 1), it is prevented from being mistakenly pressed, ensuringreliable operation. Thus, mistakes such as turning the power off whilethe device is in use can be avoided.

The embodiment has been described by taking for instance the electronicdevice including the display 5 and body 3 that can be freely turned onthe hinges to be open or closed. The present invention can be adapted toany other type of electronic device as long as a first case and a secondcase can be freely turned on hinges to be open or closed. For example,electronic device including two displays that can be freely turned onhinges to be open or closed will do.

Moreover, according to the aforesaid embodiment, the hinges are formedon the edge of the case of electronic device away from a user under thenormal specifications. Alternatively, electronic device whose right andleft cases are turned on hinges to be open or closed will do.

Functions such as left-clicking, right-clicking, and scrolling areassigned to the three operation buttons 15 a-c disposed on the frontedge about the center between the right and left sides of the body 3.

Also, as shown in FIGS. 1 and 2, there is a battery 9 provided betweenthe hinges h.

Further, as shown in FIGS. 1 and 2, a bottom surface of the lowersection 27 is not flat, and the rear end on the side of the hinges h iscurved (so that it rises a little from the surface where the electronicdevice is placed). Compared to the bottom surface of the lower section27 being flat, this structure reinforces the lower section 27 againstbending and twisting.

Also, as shown in FIG. 29, a stopper 130 is provided on a periphery ofeach hinge h facing backward of the electronic device 1. when thedisplay 5 is opened, the display 5 is prevented from opening further bythe lower edge of the display 5 meeting the stopper 130. For example, inthe present embodiment, the angle of opening (an angle formed by thebody 3 and the display 5) is restricted to 135°.

Further, as shown in FIGS. 2 and 30, tapered portions 68 and 69 areformed respectively at the front edges of the case 26 and the case 22facing with each other so that the front edges make a V-shape when thedisplay 5 is closed onto the body 3.

The tapered portion 68 is inclined upward toward the front, and thetapered portion 69 is inclined downward toward the front. The distancebetween the tapered portions 68 and 69 in a closed state, namely, whenthe case 26 and the case 22 are closed, gradually increases toward thefront.

With such a structure, even if the body 3 and the display 5 are verythin like the ones in the present embodiment, the front edge of thedisplay 5 can easily be lifted from the body 3 staying where it is byputting a finger in a V-shaped area between the tapered portions 68, 69and hooking the tapered portion 68 of the case 22 with a fingertip.

Further, as shown in FIGS. 1 and 2, various indicator lamps 17 a-17 cprovided in the front edge of the body 3 extend to the downwardlyinclined area of the front edge. Therefore, even when the display 5 isclosed as in FIG. 2, the above various indicator lamps 17 a-17 c arevisible to the user.

Although the invention has been described in its preferred form, it isto be understood that the invention is not limited to the specificembodiments thereof and various changes and modifications may be madewithout departing from the sprit and the scope of the invention.

Instead of the PC card slot of the body 3, any othersemiconductor-memory card slot may be provided.

Further, the heat-transmitting sheets 72 and 47 may be stuck to theinside of the upper section 28 and an entire surface of the inside ofthe lower section 27, respectively.

1. An electronic device comprising: a display unit; a body connected tothe display unit on one side of the body such that the electronic devicecan be opened and closed; a keyboard unit located on a front side of thebody and partly exposed to an outside for user input; a motherboardlocated in a back side of the body; and a central processor located onthe motherboard, the central processor not overlapping with the keyboardunit.
 2. The electronic device according to claim 1, wherein an upperside of the motherboard is located substantially parallel to a bottomsurface of the keyboard unit.
 3. The electronic device according toclaim 2, wherein the upper side of the motherboard partly overlaps withthe bottom surface of the keyboard unit.
 4. The electronic deviceaccording to claim 2, wherein the upper side of the motherboard does notoverlap with the bottom surface of the keyboard unit.
 5. The electronicdevice according to claim 2, wherein the central processor is located onthe upper side of the motherboard.
 6. The electronic device according toclaim 5, wherein the central processor on the mother board is locatednear to a center of the body.
 7. The electronic device according toclaim 6, further comprising: a memory unit in the back side of the bodysuch that the memory unit does not overlap with the keyboard unit andthe motherboard; and a card slot in the back side of the body such thatthe card slot does not overlap with the keyboard unit and themotherboard.
 8. The electronic device according to claim 1, furthercomprising: a heat-transmitting material covering the central processor,an elastic material configured to put the central processor in closecontact with the heat-transmitting material.
 9. The electronic deviceaccording to claim 8, further comprising: an insulating materialoverlaying on the heat-transmitting material.
 10. The electronic deviceaccording to claim 1, further comprising: a heat-generating componentlocated on an opposite side of motherboard from the central processor.11. The electronic device according to claim 10, wherein theheat-generating component on the motherboard is located near to a centerof the body.
 12. The electronic device according to claim 10, furthercomprising: a heat-transmitting material covering the heat-generatingcomponent, an elastic material configured to put the heat-generatingcomponent in close contact with the heat-transmitting material.
 13. Theelectronic device according to claim 12, further comprising: aninsulating material overlaying on the heat-transmitting material.